Tamperproof label construction

ABSTRACT

A tamperproof label is provided in which the underside of a transparent film is partially masked with a substance having limited adhesivity for the film and imprinting is applied to both the undersurface of the film and the mask. To form a tamperproof pressure-sensitive label, pressure-sensitive adhesive layer is applied over both the imprinted underside of the film and the mask, the adhesive layer having a greater adhesion for the mask than the adhesion of the mask for the undersurface of the transparent film. Once the label has been applied to a substrate any removal of the label will result in all or a portion of the adhesive layer, essentially corresponding to the pattern of the applied mask, to remain on the substrate with the printed mask. A portion of the imprinting will also be removed with the transparent film thereby destroying the intelligence of the imprint.

1 i: i mte States ate [72] Inventor John A. Pekko Whittier, Calif.

21 Appl.No. 869,764 [22] Filed Oct. 27, 1969 [45] Patented Jan. 4, 1972[73] Assignee Avery Products Corporation San Marino, Calif.

[54] TAMPERPROOF LABEL CONSTRUCTION 2,604,710 7/1952 Beune ABSTRACT: Atamperproof label is provided in which the underside of a transparentfilm is partially masked with a sub stance having limited adhesivity forthe film and imprinting is applied to both the undersurface of the filmand the mask. To form a tamperproof pressure-sensitive label,pressure-sensitive adhesive layer is applied over both the imprintedunderside of the film and the mask, the adhesive layer having a greateradhesion for the mask than the adhesion of the mask for the undersurfaceof the transparent film. Once the label has been applied to a substrateany removal of the label will result in all or a portion of the adhesivelayer, essentially corresponding to the pattern of the applied mask, toremain on the substrate with the printed mask. A portion of theimprinting will also be removed with the transparent film therebydestroying the intelligence of the imprint.

TAMPERPROOF LABEL CONSTRUCTION BACKGROUND OF THE. INVENTION The presentinvention relates to tamperproof labels particularly labels which mustbe permanently applied to a substrate.

Recently, the United States Federal Highway Administration developed aregulation requiring all manufacturers of motor vehicles to provideserial number, date and year of manufacture on a certification labelpermanently applied to the vehicle. This label certifies that thevehicle meets all applicable federal safety standards enablingpurchasers to determine by the imprinted date of manufacture whichstandards are applicable to that particular vehicle. The regulationincludes imported vehicles where the certification label should beaffixed by the foreign manufacturer who is in the best position to knowthe foreign characteristics of the vehicle. Label required must remainin place and be legible for life of the vehicle and not easilytransferable to another vehicle.

To prevent easy transferability to another vehicle the label must beessentially tamperproof. One tamperproof label has been proposed. Inthis label the required information is printed on a receptivetransparent surface having an opaque adhesive backing for application tothe substrate. Any removal of the label from the substrate will causepart of the opaque pressure sensitive material to separate fromtransparent surface and remain on the substrate forming thereby atransparent wording such as void, on the film, which, in thereby,indicates that the label had been removed from the original substrate towhich it was applied. The opaque adhesive backing, however, is readilyobtainable and the defect area can be easily mended by a reapplicationof the adhesive coating so that the label may be reused without anindication that it has been removed from the original substrate.

SUMMARY OF THE INVENTION According to the present invention there isprovided a tamperproof label construction in which any attempt to removethe label from a substrate to which it has been applied will result in adestruction of visual indicia, preferably the intelligence of suchindicia, appearing through a transparent portion of the label.

In a preferred construction, the structural member of the basic label isa self-supporting film at least a portion of which is transparent. Partof the underside of the transparent portion is printed with visualindicia and part of the underside of the transparent portion is incontact with a masking surface of limited adhesivity to the film andimprinted with a visual indicia. The imprinted and masked underside ofthe transparent film is in adhesive contact with an adhesive layerhaving upper and lower adhesive surfaces. The upper adhesive surface isin direct adhesive contact with both the imprinted transparent portionof the film and the imprinted mask and has a greater adhesive bond tothe mask than the mask has to the transparent portion of theself-supporting film. The lower adhesive surface of the adhesive layeralso has a greater adhesivity for the substrate to which the label is tobe applied than the adhesivity of the mask to the film.

When the label is removed from the substrate to which it is applied thatportion of the imprinting corresponding to the area defined by the maskwill remain on the substrate with at least part of the adhesive and thatportion of the imprinting corresponding to the masked area of thetransparent portion of the film will be removed with the self-supportingfilm with, where desired, part of the adhesive destroying thereby theintelligence of the visual indicia.

There is also provided multidestruct label systems. A preferred systemincludes the basic label described above in combination with aprotective adhesive film which allows destruction of both overprintedvisual indicia. The basis label described above has imprinted beneaththe transparent portion visual indicia which may be standard copy commonto all labels of a series. Part of the upper surface of the transparentportion thereof is in contact with a similar mask and part in contactwith a printable layer covering both the mask and the upper surface ofthe transparent portion of the self-supporting film. The printableoverlayer generally has a greater adhesion to the transparentself-supporting film than the greatest single adhesive bond provided bythe printable overlayer mask transparent film laminate. The printableoverlayer is at least transparent where the copy appears. The printableoverlayer is then printable with some intelligent visual indiciagenerally peculiar to the substrate to which it is to be applied such asa vehicle serial number and manufacturing date, designed for the printto register on portions of the printable overlayer in contact with bothfilm and mask.

The second part of the system is an adhesive self-supporting protectivewhich is at least transparent wherever visual indicia are to appear.This protective film has a greater adhesivity for the printableoverlayer than the adhesivity of the mask of the film, printableoverlayer, or both, but a lesser adhesion for the printable overlayerthan the adhesion of the printable overlayer for the film. Theprotective film also serves to protect the applied label from theelements. When the combined system is applied to a substrate removal ofthe second film removes portions the printable overlayer and anyimprinting thereon, the portions corresponding to the masked areas ofthe transparent film. As indicated above, when the self-supporting filmof the basis label is removed the visual indicia it protects is alsodestroyed DRAWINGS FIG. 1 is an expanded illustration of the severalcomponents of a preferred multidestruct tamperproof label system of thisinvention showing in addition the preferred basic tamperproof labelconstruction.

FIG. 2 is an illustration of the destruction which results from removalof the protective self-supporting, pressure-sensitive film from amultidestruct tamperproof label from a substrate.

FIG. 3 is an illustration of the destruction which then occurs uponremoval of the self-supporting transparent film of the basic labelconstruction applied to a substrate.

DESCRIPTION According to the present invention, there is provided atamperproof label that once applied to a substrate. Any attemptedremoval will cause a destruction of provided intelligent visual indicia.

Tarnperproof labels provided in accordance with the practice of thisinvention may be understood with reference to FIG. I. With referencethereto a basic tamperproof label of this invention may be fabricatedfrom a self-supporting film 10 which is at least transparent in areaswhere visual indicia are to be printed on the undersurface thereof. Apatterned mask 12 having limited or even essentially no adhesion to theselfsupporting film l0 and greater adhesion to the adhesive layer 14 isin contact with part of the undersurface of the film 10. Some visualindicia 16 such as a letter grouping shown, which may be composed ofsingle or multiple colors, a symbol, a code or any other selectedvisuallike indicia including a color coating or multicolored pattern isapplied to both mask 12 and transparent portion of film l0. Portion ofthe imprinted transparent self-supporting film and the transparentimprinted mask 12 are in adhesive contact with the upper adhesivesurface of adhesive layer.

The self-supporting film 10 may be fabricated of any material ofsufiicient integrity to provide long term protection of visual indicia16. Although cellulosic materials may be used, film I0 is preferablyfabricated from normally solid polymers such as ethylene polymers suchas polyethylene, ethylenevinyl acetate copolymers, ethylene-acrylic acidcopolymers and the like; propylene polymers such as polypropylene andethylene-propylene copolymers and the like; acrylic polymers, vinylpolymers such as polyvinyl acetate,, polyvinyl fluoride and the like;cellulose acetate, polycarbonates, polyesters, polyethers, polysulfones,styrene polymers and like polymers which offer good surface life andlong term resistance to the elements. The self-supporting film may alsobe a laminate such as a paper print laminated to at least one or betweentwo normally solid polymeric surfaces in a manner which provides awindow through which the underprinted visual indicia 16 will appear. Asindicated, areas where visual indicia 16 do not appear may be coated andprovided with other visual indicia which need not be destroyed.

Although the displaying area must be transparent it may be tinted ordyed and the like, where desired.

The nature of the mask 12 is not narrowly critical except that itsadhesivity to the upper adhesive surface adhesive layer 14 must, in thepreferred label construction of this invention, exceed its adhesivity toself-supporting film 10. It may, for in stance, be an imprinted orprintable self-supporting film such as thin polymeric membrane which haslimited or partial adhesivity to surface 10 per se or because of thepresence of a release coating such as a silicone oil. The mask ispreferably formed by the application of a transparent printable inkwhich is known to have poor adhesivity for the film surface. Forpolyester resins there can be formulated nitrocellulose, chlorinatedrubber and certain acrylic inks to provide coating or poor adhesivity tothe polyester surface. Similarly but nowise limiting, nitrocellulose andpolyamide based inks may be used with styrene polymers; chlorinatedrubber based inks may be used with polyvinyl fluoride; nitrocelluloseinks with polyvinylchloride and polyamide inks with acrylic polymers.

Also within the ambit of this invention is the use of a film 10 whichnormally has poor adhesion to adhesives and inks but good adhesion whensuitably treated or primed over a portion of the transparent surfacewill accept visual indicia with a greater tenacity than the adhesion ofapplied visual indicia to adhesive layer 14. An example is flame orcorona treated polyethylene. A portion of a clear polyethylene filmwould be treated and where treated ink and adhesive adhesion will begood but where untreated ink and adhesive adhesion will be poor. Theuntreated portion provides in essence a fragile printing which serves asthe mask surface 12 and which will remain with all or part of theadhesive when film 10 is removed.

Equally convenient is to apply a masking surface 12 to the bottom offilm 10 which has good adhesion to film 10. There may then be appliedvisual indicia which has good adhesion to masking surface 12 but pooradhesion to film 10. An adhesive is then used which will remove visualindicia from film 10 but not from the masking surface 12.

Another alternative, within the ambit of this invention, is to apply allof the visual indicia to the underside of film 10, the visual indiciahaving poor adhesion to the surface of film 10. A masking surface 12 isapplied over a portion of the visual indicia, the mask having a greateradhesivity for film 10 than for adhesive layer 14. In the alternativethe masking surface 12 may have poorer adhesion for both the film 10applied visual indicia 16. Where film 10 is removed from adhesive 14 thevisual indicia protected by the masking surface 12 remains on thesubstrate with the adhesive.

Preferably, and for convenience and ease in manufacture, mask 12 isapplied to layer 10 before imprinting occurs. The bottom surfaces offilm 10 and mask 12 are then simultaneously imprinted with any desiredvisual indicia 16 and in this instance the mask is transparent wherevisual indicia are to ap pear. After imprinting adhesive layer 14 isapplied to form the preferred composite basic tamperproof label of thisinvention. The adhesive layer 14 has two adhesive surfaces, an upper orfirst adhesive surface which will form a strong adhesive bond to film 10and mask 12 and a lower or second adhesive surface which has a greaterbond to the substrate to which contact label is to be applied than theadhesion of the mask 12 to film 10. Adhesive layer 14 may where desiredbe a laminate of two or more adhesives. More conveniently, however,adhesive surface 14 is simply a single-layer adhesive such as solvent,moisture, heat pressure activated and like adhesives. Pressuresensitiveadhesives are preferred. Where pressure-sensitive adhesives are used,the lower adhesive surface may be pro tected prior to application to asubstrate by a release coated paper (not shown) which is removed priorto label applica tion.

With reference now to FIG. 3, there may be in general demonstrated onedestruction which can occur when removal of an applied label isattempted. When the self-supporting film 10 is removed from thesubstrate 18 to which the label has been applied there will be removedwith the film 10 a portion of visual indicia 16 and a portion ofadhesive 14 and there will remain on substrate 18 a laminate composed ofa part of adhesive 14, mask 12, and part of the visual indicia 16. Thisoccurs by virtue of failure of mask 12 where it in contact with the film10. In the alternative and depending on the substrate, the visualindicia on the film is removed leaving behind all of the adhesive alongwith the mask and its visual indicia,

The basic tamperproof label construction has a wide variety of uses,particularly where the material printed thereon can be printed insequence before the adhesive surface 16 is applied and where there isonly desired destruction of the visual indicia such as a code numberwhen the label is removed.

A typical application are validation bumper stickers, for factories,schools and the like. There, typically, a numbered sticker is issued atrandom and the recipient merely recorded next to the assigned number inoffice records. Once the label is applied to the vehicle any attemptedremoval or transferral to another vehicle will result in a destructionof the code number. lt also may be used as tamperproof license plates orlicense plate validation stickers, windshield inspection stickers andthe like.

For the same or other applications, however, there may be required alabel having standardized copy and a surface to which imprinting can beapplied as the need occurs. Such is typical of the new federalregulation for automobiles wherein there is a part of every identifyinglabel a standard printed copy, and to which there must be applied aproduction date and vehicle serial number. For such applications, thereis conveniently used, in accordance with the practice of this invention,a dual destruct label system which is also illustrated in FIG. 1.

One portion of the preferred label system is, generally, a composite ofthe self-supporting film 10 and mask 12, adhesive layer 14, and printedvisual indicia 16, which can typically be a standard format providedwith all labels, To an upper surface of self-supporting film 10 theremay be applied a second mask masking 20 which like mask 12, has limitedadhesion to surface 10 and generally a greater adhesion to a printableoverlayer 22 which is transparent where indicia 16 must be visible. 1nthe alternative it may have good adhesion for surface 10 and pooradhesion for printable overlayer 22 or even poor adhesion to both.Materials used for masking surface 20 are, again, not narrowly criticaland may, fore instance by any one of the ink-polymer surfacecombinations listed above. Printable overlayer 22 may be constructed ofa thin polymeric film and the like, or is more conveniently applied as afluid coating which is at least transparent in the areas where printing16 must be visible and which when dry will form a printable surface.

Although the printable overlayer 22 must be transparent, it may betinted or colored over any portion but is in color or tint so as not toconvey to the viewer multilayer construction. In the alternative it mayprovide conspicuous alternate colored bands and the like which has adeterent effect. Included as printable overlayer 22 is an indiciaforming layer such as microspheres which when ruptured will form visualindicia.

A composite stock comprising adhesive layer 14 supported by anonadhesive release paper, visual indicia l6, masking sur face 12,supporting film 10, masking surface 20, and printable overlayer 22comprise one unit of the system. ln this instance, since the printableoverlayer 22 provides secondary protection the upper surface of film 10may be imprinted with visual indicia and the lower surface printed withindicia having a greater adhesivity for the adhesive layer 14 than forfilm 10. 1n

this system the imprinting serves as its own masking surface 12.Overlayer 22 which is initially unprinted is later imprinted by the userwith required information 26 when the item to which it is to be attachedis produced. It may contain, as in the instance of motor vehicles,serial number and date of manufacture as required by federalregulations. The second component of the system is protectiveself-supporting film 24 having one adhesive surface and which is atleast transparent where visual indicia is to be displayed. It should beconstructed of a material resistant to the elements and may beidentical, or different, from construction of the self-supporting film10. As indicated, protective self-supporting film 24 must betransparent, at least at the zones where imprinted visual indicia l6 andapplied printed visual indicia 26 are to appear. As indicated, theprotective film 24 has applied on the undersurface thereof an adhesive,preferably, a pressure-sensitive adhesive which will more stronglyadhere to printable overlayer 22 than the adhesion of mask 20 toself-supporting film l0, printable overlayer 22, or both. The protectivefilm 24 is applied to the imprinted first component of the systemgenerally after it has been applied to the substrate, or in thealternative, applied to the base label on a common pressure-sensitiveadhesive release surface, such as a silicone coated paper, and bothparts jointly applied to the substrate upon removal of the releasesurface.

With reference now to FIG. 2, when the protective film 24 is removedfrom the substrate, there is removed with it a portion of the imprintedindicia 26 and a portion of the printable overlayer 22, and maskingsurface 20, leaving behind a portion of the printed indicia 26 on theremaining printed overlayer 22 and exposing the self-supporting film 10which still protects the integrity of imprinting 16. In the alternative,the masking surface may remain on the surface of self-supporting film 10when the protective self-supporting film 24 is removed carrying with ita portion of the printed overlayer 20.

When an attempt is made to remove film surface 10 from the substrate,destruction which occurs is that illustrated in FIG. 3. The removedself-supporting film 10 carries with it a least a portion of theimprinted indicia 26, printable overlayer 22, a portion of the lowervisual indicia l6, and leaving behind part of visual indicia 16 and allor part of adhesive layer 14 on the substrate.

In the alternative, the upper surface of self-supporting film 10 may beentirely coated with a printable overlayer 22 having poor adhesion tofilm 10. A mask 22 is applied over a portion of printable overlayer 20,the mask having, however, poorer adhesion to the adhesive surface of theprotective self-supporting film 24 than the adhesion printable overlayer20 to film 10. When film 24 is lifted from a final applied labelassembly the failure occurs at the mask which remains behind with aportion of printable overlayer 22 on film 10.

In another alternative a masking surface 22 having good adhesion to boththe film 10 and a printable overlayer 20 may be applied to part of film10 as a primer. As indicated printable overlayer 20 has good adhesion tomasking surface 22, this ad hesion being greater adhesion to theadhesive of protective film 24. The printable overlayer, however, has agreater adhesion to protective film 24 than to film l0. Removal ofprotective film 24 then results in a removal of that portion ofprintable overlayer 20 which is not in contact with masking surface 22.

Although the tamperproof label systems of this invention have beendescribed in terms of end use construction, it is within the ambit tosupply the systems as several component for imprinting and assembly bythe user.

The basic tamperproof label may be provided as a twocomponent system.The first component would comprise the at least partially transparentself-supporting film 10 and applied masking surface 12. The secondcomponent would comprise adhesive layer 14. The film 10 and maskingsurface 12 would then be reverse printed and the tamperproof labelconstructed by application of adhesive layer 14. The composite ofself-supporting film 10 and masking surface 12 could be coated withindicia forming microspheres which could be activated to produce visualindicia before or after application of the adhe sive layer 14 providedthe bond of the microspheres to the underside of self-supporting film 10exceeds the bond of the adhesive to the microsphere layer.

In the alternative component could be the self-supporting film 10 andmasking surface 12, the masking surface having strong adhesion to thefilm 10. In this instance there would be used an ink having strongadhesion to the masking surface 12 but weak adhesion to film 10. In thisinstance there may be used indicia forming microspheres which only bondwell to the masking surface 12 and which when ruptured will producevisual indicia. Adhesive layer 14 would then in the final assemblyremove the imprinted visual indicia whenever an attempt is made toremove the applied label from a substrate.

It may also be provided as a three-component system. The first componentwould be self-supporting film 10, at least one surface of which isprintable or capable of formingvisual indicia by application ofsufficient pressure such as by the use of rupturable microspheres. Thesecond component would be the masking surface 12 and the third, adhesivelayer 14. Imprinting would then be applied to self-supporting film 10and the tamperproof label formed as a laminate of printed film l0,masking surface 12 and adhesive layer 14, the masking surface 12 andadhesive layer 14 contacting the imprinted portion of film 10. In thisinstance masking surface 12 serves to insulate a portion of theimprinting from an adhesive surface having a greater adhesion to aselected applied visual indicia than the adhesion of the visual indiciafor film 10.

The three-component assembly may be used in which imprinting is appliedto the combination of film 10 and masking surface 12. In this instanceeither the masking surface 12 or the imprinting on that portion of thefilm in contact with the adhesive layer would be removed.

It will be well appreciated that these multicomponent systems are utilefor the ultimate construction of the multidestruct label systems of thisinvention.

What is claimed is:

l. A composite tamperproof label construction comprising:

a. a self-supporting film at least a portion of which is transparent andhaving at least one surface imprinted with first visual indicia; amasking surface in contact with at least part of at least one surface ofthe transparent portion of a said self-supporting film said maskingsurface at least in contact with a second imprinted visual indicia; and

c. an adhesive layer having a first adhesive surface in contact with thetransparent portion of said self-supporting film and said maskingsurface and a second adhesive surface for contact with a substrate; saidmasking surface and said first and second adhesive surfaces cooperatingto allow a portion of the total visual indicia and at least a portion ofsaid first and second adhesive surfaces to remain on the substrate towhich the composite tamperproof label is applied when the label isremoved therefrom.

2. A composite tamperproof label construction as claimed in claim 1 inwhich the masking surface is the separable imprinted second visualindicia.

3. A composite tamperproof label construction as claimed in claim l inwhich:

a. a part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in contact with a second masking surface; and

. a printable overlayer, at least transparent where visual indicia is toappear through the transparent portion of said self-supporting film, isin contact with the exposed transparent portion of the self-supportingfilm and said second masking surface, the adhesivity of said printableoverlayer for the exposed transparent surface exceeding the maximuminterlayer adhesion available from the laminate comprising saidprintableoverlayer, said second masking surface and the exposed transparentportion of said self supporting film.

4. A composite tamperproof label as claim claim 3 in combination with aself-supporting protective film, transparent at least where visualindicia is to appear therethrough, said protective film having anadhesive surface for contact with said printable overlayer, theadhesivity of said adhesive surface having a greater adhesivity for saidprintable overlayer than the maximum interlayer adhesive bond providedby the laminate comprising the overlayer, second masking surface andexposed transparent portion of said self supporting film, but less thanthe adhesivity of said printable overlayer for the exposed transparentsurface.

5. A tamperproof label construction as claimed in claim 1 in which:

a. at least part of the exposed transparent portion of theselfsupporting film opposed to the surface in contact with the maskingsurface is in contact with a printable overlayer; and

b. a second masking surface is in contact with a portion of saidprintable overlayer.

6. A tamperproof label construction as claimed in claim 5 in combinationwith a self-supporting protective, transparent at least where visualindicia is to appear therethrough, said protective film having anadhesive surface for contact with said printable overlayer and saidsecond masking surface, the adhesivity of said adhesive surface for saidprintable overlay ex ceeding the adhesivity of said printable overlayfor the exposed portion of said transparent film and less than theminimum interlayer bond available from a laminate comprising saidprintable overlayer, said second masking surface and the exposedtransparent portion of said self-supporting film.

7. A composite tamperproof label construction comprising:

a. a self-supported film at least a portion of which is transparent andimprinted with visual indicia;

b. a masking surface imprinted with visual indicia in contact with partof the transparent portion of said self-supporting film;

c. an adhesive layer having a first adhesive surface in adhesive contactwith at least the transparent portion of said self-supporting film andsaid imprinted masking surface; the adhesivity of said first adhesivelayer for said imprinted masking surface exceeding the contact adherenceof said imprinted masking surface for the transparent portion of saidfilm, and a second adhesive surface, having a greater adhesivity forsubstrate to which the label is to be applied than the contact adherenceof said masking surface for the transparent portion of said film.

8. A composite tamperproof label construction as claimed in claim 7 inwhich the masking surface is transparent and imprinted on the surfacethereof in contact with the adhesive layer.

9. A composite tamperproof label construction as claimed in claim 8 inwhich:

a. a part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in contact with a second masking surface; and

b. a printable overlayer, at least transparent where visual indicia isto appear through the transparent portion of said self-supporting film,is in contact with the exposed transparent portion of theself-supporting film and said second masking surface, the adhesivity ofsaid printable overlayer for the exposed transparent surface exceedingthe maximum interlayer adhesion available from the laminate comprisingsaid printable overlayer, said second masking surface and the exposedtransparent portion of said selfsupporting film.

10. A composite tamperproof label as claimed in claim 9 in combinationwith a self-supporting protective film, transparent at least wherevisual indicia is to appear therethrough, said protective film having anadhesive surface for contact with said printable overlayer, theadhesivity of said adhesive surface having a greater adhesivity for saidprintable overlayer than the maximum interlayer adhesive bond providedby the laminate comprising the overlayer, second masking surface andexposed transparent portion of said self-supporting film, but less thanthe adhesivity of said printable overlayer for the exposed transparentsurface.

11. A composite tamperproof label construction as claimed in claim 8 inwhich:

a. part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in adhesive contact with a second masking surface; and

b. a printable overlay, at least transparent where visual indicia is toappear through the transparent portion of said self-supporting film, isin adhesive contact with said second masking surface and in directadhesive contact with part of the exposed transparent portion of saidselfsupporting film.

12. A composite tamperproof label construction as claimed in claim 11 incombination with a self-supporting protective film, transparent at leastwhere visual indicia is to appear therethrough, said protective filmproviding an adhesive surface for contact with said printable overlay,the adhesivity of said adhesive surface to said printable overlay,exceeding the adhesivity of the printable overlayer indirect contactwith the exposed transparent portion of said self-supporting film butless than the adhesivity of the printable overlay for said secondmasking surface and the adhesivity of said second masking surface forthe exposed transparent portion of said self-supporting film.

13. A tamperproof label construction as claimed in claim 8 in which:

a. at least part of the exposed transparent portion of theselfsupporting film opposed to the surface in contact with the maskingsurface is in contact with a printable overlayer; and

b. a second masking surface is in contact with a portion of saidprintable overlayer.

14. A tamperproof label construction as claimed in claim 13 incombination with a self-supporting protective, transparent at leastwhere visual indicia is to appear therethrough, said protective filmhaving an adhesive surface for contact with said printable overlayer andsaid second masking surface, the adhesivity of said adhesive surface forsaid printable overlay for the exposed portion of said transparent filmand less than the minimum interlayer bond available from a laminatecomprising said printable overlay, said second masking surface and theexposed transparent portion of said self-supporting film.

15. A composite tamperproof label construction as claimed in claim 7 inwhich:

a. a part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in contact with a second masking surface; and

b. a printable overlayer, at least transparent where visual indicia isto appear through the transparent portion of said self-supporting film,is in contact with the exposed transparent portion of theself-supporting film and said second masking surface, the adhesivity ofsaid printable overlayer for the exposed transparent surface exceedingthe maximum interlayer adhesion available from the laminate comprisingsaid printable overlayer, said second masking surface and the exposedtransparent portion of said selfsupporting film.

16. A composite tamperproof label as claimed in claim 15 in combinationwith a self-supporting protective film, transparent at least wherevisual indicia is to appear therethrough, said protective film having anadhesive surface for contact with said printable overlayer, theadhesivity of said adhesive surface having a greater adhesivity for saidprintable overlayer than the maximum interlayer adhesive bond providedby the laminate comprising the overlayer, second masking surface andexposed transparent portion of said self-supporting film, but less thanthe adhesivity of said printable overlayer of the exposed transparentsurface.

17. A composite tamperproof label construction as claimed in claim 7 inwhich:

a. part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in adhesive contact with a second masking surface; and

b. a printable overlay, at least transparent where visual indicia is toappear through transparent portion of said selfsupporting film, is inadhesive contact with said second masking surface and in direct adhesivecontact with part of the exposed transparent portion of saidself-supporting film.

18. A composite tamperproof label construction as claimed in claim 17 incombination with a self-supporting protective film, transparent at leastwhere visual indicia is to appear therethrough, said protective filmproviding an adhesive surface for contact with said printable overlay,the adhesivity of said adhesive surface to said printable overlay,exceeding the adhesivity of the printable overlayer in direct contactwith the exposed transparent portion of said self-supporting film butless than the adhesivity of the printable overlay for said secondmasking surface and the adhesivity of said second masking surface forthe exposed transparent portion of said self-supporting film.

19. A tamperproof label construction as claimed in claim 7 in which:

a. at least part of the exposed transparent portion of theselfsupporting film opposed to the surface in contact with the maskingsurface is in contact with a printable overlayer; and

b. a second masking surface is in contact with a portion of saidprintable overlayer.

20. A tamperproof label construction as claimed in claim 19 incombination with a self-supporting protective, transparent at leastwhere visual indicia is to appear therethrough, said protective filmhaving an adhesive surface for contact with said printable overlayer andsaid second masking surface, the adhesivity of said adhesive surface forsaid printable overlay exceeding the adhesivity of said printableoverlay for the exposed portion of said transparent film and less thanthe minimum interlayer bond available from a laminate comprising saidprintable overlay, said second masking surface and the exposedtransparent portion of said self-supporting film.

21. A composite tamperproof label construction comprising:

a. a self-supported film at least a portion of which is transparent andimprinted with visual indicia on at least one surface of the transparentportion;

b. a masking surface in contact with at least part of the visual indiciaprovided on at least one imprinted surface;

0. a adhesive layer having a first adhesive surface in contact with saidmasking surface and part of the imprinting on the surface of thetransparent portion of said self-supporting film in contact with saidmasking surface, said first adhesive layer having a greater adhesivityfor the imprinted visual indicia on the unmasked portion of thetransparent film than the adhesivity of the imprinted visual indicia forthe transparent portion of said self-supporting film and a secondadhesive surface having a greater adhesivity for a substrate to whichthe label is to be applied than adhesivity of the unmasked printedindicia for the transparent portion of said self-supporting film.

22. A composite tamperproof label construction as claimed in claim 21 inwhich:

a. a part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in contact with a second masking surface; and

b. a printable overlayer, at least transparent where visual indicia isto appear through the transparent portion of said selfsupporting film,in contact with the exposed transparent portion of the self-supportingfilm and said second masking surface, the adhesivity of said printableoverlayer for the exposed transparent surface exceeding the maximuminterlayer adhesion available from the laminate comprising saidprintable overlayer, said second masking surface and the exposedtransparent portion of said selfsupporting film.

23. A composite tamperproof label as claimed in claim 22 in combinationwith a self-supporting protective film, transparent at least wherevisual indicia is to appear therethrough, said protective film having anadhesive for contact with said printable overlayer, the adhesivity ofsaid adhesive surface having a greater adhesivity for said printableoverlayer than the maximum interlayer adhesive bond provided by thelaminate comprising the overlayer, second masking surface and exposedtransparent portion of said self-supporting film, but less than theadhesivity of said printable overlayer for the exposed transparentsurface.

24. A composite tamperproof label construction as claimed in claim 21 inwhich:

a. part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in adhesive contact with a second masking surface; and

b. a printable overlay, at least transparent where visual indicia is toappear through the transparent portion of said self-supporting film, isin adhesive contact with said second masking surface and in directadhesive contact with part of the exposed transparent portion of saidselfsupporting film.

25. A composite tamperproof label construction as claimed in claim 24 incombination with a self-supporting protective film, transparent at leastwhere visual indicia is to appear therethrough, said protective filmproviding an adhesive surface for contact with said printable overlay,the adhesivity of said adhesive surface to said printable overlayexceeding the adhesivity of the printable overlayer in direct contactwith the exposed transparent of said self-supporting film but less thanthe adhesivity of the printable overlay for said second masking surfaceand the adhesivity of said second masking surface for the exposedtransparent portion of said self-supporting film.

26. A composite tamperproof label construction as claimed in claim 21 inwhich:

a. part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in adhesive contact with a second masking surface; and

b. a printable overlay, at least transparent where visual indicia is toappear through the transparent portion of said self-supporting film, isin adhesive contact with said second masking surface and in directadhesive contact with part of the exposed transparent portion of saidselfsupporting film.

27. A composite tamperproof label construction as claimed in claim 26 incombination with a self-supporting protective film, transparent at leastwhere visual indicia is to appear therethrough, said protective filmproviding an adhesive surface for contact with said printable overlay,the adhesivity of said adhesive surface to said printable overlayexceeding the adhesivity of the printable overlayer in direct contactwith the exposed transparent portion of said self-supporting film butless than the adhesivity of the printable overlay for said secondmasking surface and the adhesivity of said second masking surface forthe exposed transparent portion of said self-supporting film.

28. A tamperproof label construction as claimed in claim 21 in which:

a. at least part of the exposed transparent portion of theselfsupporting film opposed to the surface in contact with the maskingsurface is in contact with a printable overlayer; and

b. a second masking surface is in contact with a portion of saidprintable overlayer.

29. A tamperproof label construction as claimed in claim 28 incombination with a self-supporting protective, transparent at leastwhere visual indicia is to appear therethrough, said protective filmhaving an adhesive surface for contact with said printable overlayer andsaid second masking surface, the adhesivity of said adhesive surface forsaid printable overlay exceeding the adhesivity of said printableoverlay for the exposed portion of said transparent film and less thanthe minimum interlayer bond available from a laminate comprising saidprintable overlay, said second masking surface and the exposedtransparent portion of said self-supporting film.

30. A composite tamperproof label construction comprismg:

a. a self-supporting film at least a portion of which is transparent andimprinted with visual indicia on at least one surface of the transparentportion;

b. a masking surface imprinted with visual indicia in adhesive contactwith at least one imprinted surface of the transparent portion of saidself-supporting film;

c. an adhesive layer having a first adhesive surface in contact withsaid masking surface and the imprinted surface of the transparentportion of said self-supporting film, the adhesion of said firstadhesive surface for the imprinted visual indicia on transparent portionof said self-supporting surface exceeding the adhesion of the imprintedvisual indicia for the transparent portion of said self-supporting filmand a second adhesive surface having a greater adhesion for a substrateto which the label is to be applied than the adhesion of the imprintedvisual indicia for the transparent portion of said self-supporting film.

31. A composite tamperproof label construction as claimed in claim 30 inwhich said masking surface is transparent and imprinted on the surfacethereof in contact with said adhesive layer.

32. A composite tamperproof label construction as claimed in claim 30 inwhich:

a. a part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in contact with a second masking surface; and

b. a printable overlayer, at least transparent where visual indicia isto appear through the transparent portion of said self-supporting film,is in contact with the exposed transparent portion of theself-supporting film and said second masking surface, the adhesivity ofsaid printable overlayer for the exposed transparent surface exceedingthe maximum interlayer adhesion available from the laminate comprisingsaid printable overlayer, said second masking surface and the exposedtransparent portion of said selfsupporting film.

33. A composite tamperproof label as claimed in claim 32 in combinationwith a self-supporting protective film, transparent at least wherevisual indicia is to appear therethrough, said protective film having anadhesive surface for contact with said printable overlayer, theadhesivity of said adhesive surface having a greater adhesivity for saidprintable overlayer than the maximum interlayer adhesive bond providedby the laminate comprising the overlayer, second masking surface andexposed transparent portion of said self-supporting film, but less thanthe adhesivity of said printable overlayer for the exposed transparentsurface 34. A composite tamperproof label construction as claimed inclaim 30 in which:

a. part of the surface of the exposed transparent portion of theself-supporting film opposed to the surface in contact with the maskingsurface is in adhesive contact with a second masking surface; and

b. a printable overlay, at least transparent where visual indicia is toappear through the transparent portion of said self-supporting film, isin adhesive contact with said second masking surface and in directadhesive contact with part of the exposed transparent portion of saidselfsupporting film.

35. A composite tamperproof label construction as claimed in claim 34 incombination with a self-supporting protective film, transparent at leastwhere visual indicia is to appear therethrough, said protective filmproviding an adhesive surface for contact with said printable overlay,the adhesivity of said adhesive surface to said printable overlayexceeding the adhesivity of the printable overlayer in direct contactwith the exposed transparent portion of said self-supporting film butless than the adhesivity of the printable overlay for said secondmasking surface and the adhesivity of said second masking surface forthe exposed transparent portion of said self-supporting film.

36. A tamperproof label construction as claimed in claim 30 in which:

a. at least part of the exposed transparent portion of theselfsupporting film opposed to the surface in contact with the maskingsurface is in contact with a printable overlayer; and

b. a second masking surface is in contact with a portion of saidprintable overlayer.

37. A tamperproof label construction as claimed in claim 36 incombination with a self-supporting protective, transparent at leastwhere visual indicia is to appear therethrough, said protective filmhaving an adhesive surface for contact with said printable overlayer andsaid mcond masking surface for contact with said printable overlayer andsaid second masking surface, the adhesivity of said adhesive surface forsaid printable overlay exceeding the adhesivity of said printableoverlay for the exposed portion of said transparent film and less thanthe minimum interlayer bond available from a laminate comprising saidprintable overlay, said second masking surface and the exposedtransparent portion of said self-supporting film.

38. A composite for construction of a tamperproof label which comprises:

a. a self-supporting film at least a portion of which is transparent andadapted to accept imprinting;

b. a transparent masking surface in contact with part of the transparentportion of said self-supporting film said masking surface adapted toaccept imprinting; and

c. an adhesive layer having a first adhesive surface for contact withsaid self-supporting film and said masking surface, the adhesivity ofsaid first adhesive surface for said masking surface exceeding thecontact adherence of said masking surface for the transparent portion ofsaid selfsupporting film and a second adhesive surface adapted forcontact to a substrate, the adhesivity of said second adhesive surfacefor the substrate to which it is to be applied exceeding the contactadherence of said masking surface for the transparent portion of saidself-supporting film.

39. A composite for construction of a tamperproof label which comprises:

a. a self-supporting film at least a portion of which is transparent andadapted to accept imprinting;

b. a transparent masking surface in adhesive contact with part of thetransparent portion of said self-supporting film; said masking surfaceadapted to accept imprinting; and

c. an adhesive layer having a first adhesive surface adapted for contactwith the transparent portion of said self-supporting film and saidmasking surface; the adhesion of said first adhesive surface for atleast one printable visual indicia exceeding the adhesivity of theprintable indicia for the transparent portion of said self-supportingfilm and a second adhesive surface for contact to a substrate, theadhesion of said second adhesive surface for the sub strate to which itis to be applied exceeding the adhesivity of the printable indicia forthe transparent portion of said film.

40. A composite for construction of a tamperproof label which comprises:

a. a self-supporting film at least a portion of which is transparent andadapted to accept imprinting;

b. a transparent masking surface in adhesive contact with part of thetransparent portion of said self-supporting film; said masking surfaceadapted to accept imprinting; and

c. an adhesive layer having a first adhesive surface adapted for contactwith the transparent portion of said self-supporting film and saidmasking surface; the adhesion of said first adhesive surface for atleast one printable visual indicia exceeding the adhesivity of theprintable indicia for the transparent portion of said masking surfaceand a second adhesive surface for contact to a substrate the adhesion ofsaid second adhesive surface for the substrate to which it is to beapplied exceeding the adhesivity of the printable indicia for saidmasking surface.

41. A composite for construction of a tamperproof label which comprises:

a. a self-supporting film at least a portion of which is transparent andadapted to accept imprinting;

b. a self-supporting masking surface adapted to be applied over a partof the transparent portion of said self-supporting film; and

. an adhesive layer having a first adhesive surface adapted for contactwith the transparent portion of said self-supporting film and saidmasking surface, the adhesivity of said first adhesive surface for avisual indicia printable on the transparent portion of saidself-supporting film exceeding the adhesivity of said visual indicia forsaid selfsupporting film and a second adhesive surface adapted foradhesive contact with a substrate, the adhesion of said second adhesivesurface to which it is to be applied exceeding the adhesivity of saidvisual indicia for the trans parent portion of said self-supportingfilm.

' 22 3 3 UNITED STATES PATENT OFFICE CERTIFICATE OF'QORRECTION PatentNo. 3,631,617 Dated Jan. 4, 1972 Inventor(s) John Pekko It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Col. 1, line 29, change "thereby" to --theory-- .1

line 71, after "indicia", insert --as well as undera printed visualindicia.--

line 71, change "basis" to -basic-- Col. 2, line 17, change "of" to--for-- line 26, change "basis" to --basic-- line 44, after "substrate",eliminate Any" and insert --any-- line 61, change "Portion" toPortions-'- line 64, after "layer", insert '--14- line 73, after"acetate," insert ---polyvinyl chloride-- Col. 3, line 54, change"poorer".to --poor-- line 57, after "12", insert --is removed with film10 and the portion of the imprinted visual indicia unprotected bymasking surface 12-- line 69, change "contact" to "the-- Col. 4, line62, after "is", insert --preferably, uniform-- line 53, change "fore" to"for-'- 001.. 7, line 3, change "as claim" to --as claimed inline 32,"change 1 overlayer" to --overlay-- Col. 9, lineg' 5 6, change "a" to--an-- Col. 10, line 40, after "transparent", insert --portion-- 1 Col.12, line 26, after "surface", remove "for contact with said printableoverlayer and said second masking surface" Signed and sealed this 9thday of January 1973.

(SEAL) Attest:

EDWARD M.FLETCUER ,JR. ROBERT GOTTSCHALK -/\ttesting OfficerCommissioner of Patents

1. A composite tamperproof label construction comprising: a. aself-supporting film at least a portion of which is transparent andhaving at least one surface imprinted with first visual indicia; b. amasking surface in contact with at least part of at least one surface ofthe transparent portion of a said selfsupporting film said maskingsurface at least in contact with a second imprinted visual indicia; andc. an adhesive layer having a first adhesive surface in contact with thetransparent portion of said self-supporting film and said maskingsurface and a second adhesive surface for contact with a substrate; saidmasking surface and said first and second adhesive surfaces cooperatingto allow a portion of the total visual indicia and at least a portion ofsaid first and second adhesive surfaces to remain on the substrate towhich the composite tamperproof label is applied when the label isremoved therefrom.
 2. A composite tamperproof label construction asclaimed in claim 1 in which the masking surface is the separableimprinted second visual indicia.
 3. A composite tamperproof labelconstruction as claimed in claim 1 in which: a. a part of the surface ofthe exposed transparent portion of the self-supporting film opposed tothe surface in contact with the masking surface is in contact with asecond masking surface; and b. a printable overlayer, at leasttransparent where visual indicia is to appear through the transparentportion of said self-supporting film, is in contact with the exposedtransparent portion of the self-supporting film and said second maskingsurface, the adhesivity of said printable overlayer for the exposedtransparent surface exceeding the maximum interlayer adhesion availablefrom the laminate comprising said printable overlayer, said secondmasking surface and the exposed transparent portion of saidself-supporting film.
 4. A composite tamperproof label as claim claim 3in combination with a self-supporting protective film, transparent atleast where visual indicia is to appear therethrough, said protectivefilm having an adhesive surface for contact with said printableoverlayer, the adhesivity of said adhesive surface having a greateradhesivity for said printable overlayer than the maximum interlayeradhesive bond provided by the laminate comprising the overlayer, secondmasking surface and exposed transparent portion of said self supportingfilm, but less than the adhesivity of said printable overlayer for theexposed transparent surface.
 5. A tamperproof label construction asclaimed in claim 1 in which: a. at least part of the exposed transparentportion of the self-supporting film opposed to the surface in contactwith the masking surface is in contact with a printable overlayer; andb. a second masking surface is in contact with a portion of saidprintable overlayer.
 6. A tamperproof label construction as claimed inclaim 5 in combination with a self-supporting protective, transparent atleast where visual indicia is to appear therethrough, said protectivefilm having an adhesive surface for contact with said printableoverlayer and said second masking surface, the adhesivity of saidadhesive surface for said printable overlay exceeding the adhesivity ofsaid printable overlay for the exposed portion of said transparent filmand less than the minimum interlayer bond available from a laminatecomprising said printable overlayer, said second masking surface and theexposed transparent portion of said self-supporting film.
 7. A compositetamperproof label construction comprising: a. a self-supported film atleast a portion of which is transparent and imprinted with visualindicia; b. a masking surface imprinted with visual indicia in contactwith part of the transparent portion of said self-supporting film; c. anadhesive layer having a first adhesive surface in adhesive contact withat least the transparent portion of said self-supporting film and saidimprinted masking surface; the adhesivity of said first adhesive layerfor said imprinted masking surface exceeding the contact adherence ofsaid imprinted masking surface for the transparent portion of said film,and a second adhesive surface, having a greater adhesivity for substrateto which the label is to be applied than the contact adherence of saidmasking surface for the transparent portion of said film.
 8. A compositetamperproof label construction as claimed in claim 7 in which themasking surface is transparent and imprinted on the surface thereof incontact with the adhesive layer.
 9. A composite tamperproof labelconstruction as claimed in claim 8 in which: a. a part of the surface ofthe exposed transparent portion of the self-supporting film opposed tothe surface in contact with the masking surface is in contact with asecond masking surface; and b. a printable overlayer, at leasttransparent where visual indicia is to appear through the transparentportion of said self-supporting film, is in contact with the exposedtransparent portion of the self-supporting film and said second maskingsurface, the adhesivity of said printable overlayer for the exposedtransparent surface exceeding the maximum interlayer adhesion availablefrom the laminate comprising said printable overlayer, said secondmasking surface and the exposed transparent portion of saidself-supporting film.
 10. A composite tamperproof label as claimed inclaim 9 in combination with a self-supporting protective film,transparent at least where visual indicia is to appear therethrough,said protective film having an adhesive surface for contact with saidprintable overlayer, the adhesivity of said adhesive surface having agreater adhesivity for said printable overlayer than the maximuminterlayer adhesive bond provided by the laminate comprising theoverlayer, second masking surface and exposed transparent portion ofsaid self-supporting film, but less than the adhesivity of saidprintable overlayer for the exposed transparent surface.
 11. A compositetamperproof label construction as claimed in claim 8 in which: a. partof the surface of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is inadhesive contact with a second masking surface; and b. a printableoverlay, at least transparent where visual indicia is to appear throughthe transparent portion of said self-supporting film, is in adhesivecontact with said second masking surface and in direct adhesive contactwith part of the exposed transparent portion of said self-supportingfilm.
 12. A composite tamperproof label construction as claimed in claim11 in combination with a self-supporting protective film, transparent atleast where visual indicia is to appear therethrough, said protectivefilm providing an adhesive surface for contact with said printableoverlay, the adhesivity of said adhesive surface to said printableoverlay, exceeding the adhesivity of the printable overlayer in directcontact with the exposed transparent portion of said self-supportingfilm but less than the adhesivity of the printable overlay for saidsecond masking surface and the adhesivity of said second masking surfacefor the exposed transparent portion of said self-supporting film.
 13. Atamperproof label construction as claimed in claim 8 in wHich: a. atleast part of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is incontact with a printable overlayer; and b. a second masking surface isin contact with a portion of said printable overlayer.
 14. A tamperprooflabel construction as claimed in claim 13 in combination with aself-supporting protective, transparent at least where visual indicia isto appear therethrough, said protective film having an adhesive surfacefor contact with said printable overlayer and said second maskingsurface, the adhesivity of said adhesive surface for said printableoverlay for the exposed portion of said transparent film and less thanthe minimum interlayer bond available from a laminate comprising saidprintable overlay, said second masking surface and the exposedtransparent portion of said self-supporting film.
 15. A compositetamperproof label construction as claimed in claim 7 in which: a. a partof the surface of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is incontact with a second masking surface; and b. a printable overlayer, atleast transparent where visual indicia is to appear through thetransparent portion of said self-supporting film, is in contact with theexposed transparent portion of the self-supporting film and said secondmasking surface, the adhesivity of said printable overlayer for theexposed transparent surface exceeding the maximum interlayer adhesionavailable from the laminate comprising said printable overlayer, saidsecond masking surface and the exposed transparent portion of saidself-supporting film.
 16. A composite tamperproof label as claimed inclaim 15 in combination with a self-supporting protective film,transparent at least where visual indicia is to appear therethrough,said protective film having an adhesive surface for contact with saidprintable overlayer, the adhesivity of said adhesive surface having agreater adhesivity for said printable overlayer than the maximuminterlayer adhesive bond provided by the laminate comprising theoverlayer, second masking surface and exposed transparent portion ofsaid self-supporting film, but less than the adhesivity of saidprintable overlayer of the exposed transparent surface.
 17. A compositetamperproof label construction as claimed in claim 7 in which: a. partof the surface of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is inadhesive contact with a second masking surface; and b. a printableoverlay, at least transparent where visual indicia is to appear throughtransparent portion of said self-supporting film, is in adhesive contactwith said second masking surface and in direct adhesive contact withpart of the exposed transparent portion of said self-supporting film.18. A composite tamperproof label construction as claimed in claim 17 incombination with a self-supporting protective film, transparent at leastwhere visual indicia is to appear therethrough, said protective filmproviding an adhesive surface for contact with said printable overlay,the adhesivity of said adhesive surface to said printable overlay,exceeding the adhesivity of the printable overlayer in direct contactwith the exposed transparent portion of said self-supporting film butless than the adhesivity of the printable overlay for said secondmasking surface and the adhesivity of said second masking surface forthe exposed transparent portion of said self-supporting film.
 19. Atamperproof label construction as claimed in claim 7 in which: a. atleast part of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is incontact with a printable overlayer; and b. a second masking surface isin contact with a portion of said printable overlayer.
 20. A tamperprooflabel constructiOn as claimed in claim 19 in combination with aself-supporting protective, transparent at least where visual indicia isto appear therethrough, said protective film having an adhesive surfacefor contact with said printable overlayer and said second maskingsurface, the adhesivity of said adhesive surface for said printableoverlay exceeding the adhesivity of said printable overlay for theexposed portion of said transparent film and less than the minimuminterlayer bond available from a laminate comprising said printableoverlay, said second masking surface and the exposed transparent portionof said self-supporting film.
 21. A composite tamperproof labelconstruction comprising: a. a self-supported film at least a portion ofwhich is transparent and imprinted with visual indicia on at least onesurface of the transparent portion; b. a masking surface in contact withat least part of the visual indicia provided on at least one imprintedsurface; c. a adhesive layer having a first adhesive surface in contactwith said masking surface and part of the imprinting on the surface ofthe transparent portion of said self-supporting film in contact withsaid masking surface, said first adhesive layer having a greateradhesivity for the imprinted visual indicia on the unmasked portion ofthe transparent film than the adhesivity of the imprinted visual indiciafor the transparent portion of said self-supporting film and a secondadhesive surface having a greater adhesivity for a substrate to whichthe label is to be applied than adhesivity of the unmasked printedindicia for the transparent portion of said self-supporting film.
 22. Acomposite tamperproof label construction as claimed in claim 21 inwhich: a. a part of the surface of the exposed transparent portion ofthe self-supporting film opposed to the surface in contact with themasking surface is in contact with a second masking surface; and b. aprintable overlayer, at least transparent where visual indicia is toappear through the transparent portion of said self-supporting film, incontact with the exposed transparent portion of the self-supporting filmand said second masking surface, the adhesivity of said printableoverlayer for the exposed transparent surface exceeding the maximuminterlayer adhesion available from the laminate comprising saidprintable overlayer, said second masking surface and the exposedtransparent portion of said self-supporting film.
 23. A compositetamperproof label as claimed in claim 22 in combination with aself-supporting protective film, transparent at least where visualindicia is to appear therethrough, said protective film having anadhesive for contact with said printable overlayer, the adhesivity ofsaid adhesive surface having a greater adhesivity for said printableoverlayer than the maximum interlayer adhesive bond provided by thelaminate comprising the overlayer, second masking surface and exposedtransparent portion of said self-supporting film, but less than theadhesivity of said printable overlayer for the exposed transparentsurface.
 24. A composite tamperproof label construction as claimed inclaim 21 in which: a. part of the surface of the exposed transparentportion of the self-supporting film opposed to the surface in contactwith the masking surface is in adhesive contact with a second maskingsurface; and b. a printable overlay, at least transparent where visualindicia is to appear through the transparent portion of saidself-supporting film, is in adhesive contact with said second maskingsurface and in direct adhesive contact with part of the exposedtransparent portion of said self-supporting film.
 25. A compositetamperproof label construction as claimed in claim 24 in combinationwith a self-supporting protective film, transparent at least wherevisual indicia is to appear therethrough, said protective film providingan adhesive surface for contact with said printable overlay, theadhesivity of said adhesive surface to said printable overlay exceedingthe adhesivity of the printable overlayer in direct contact with theexposed transparent of said self-supporting film but less than theadhesivity of the printable overlay for said second masking surface andthe adhesivity of said second masking surface for the exposedtransparent portion of said self-supporting film.
 26. A compositetamperproof label construction as claimed in claim 21 in which: a. partof the surface of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is inadhesive contact with a second masking surface; and b. a printableoverlay, at least transparent where visual indicia is to appear throughthe transparent portion of said self-supporting film, is in adhesivecontact with said second masking surface and in direct adhesive contactwith part of the exposed transparent portion of said self-supportingfilm.
 27. A composite tamperproof label construction as claimed in claim26 in combination with a self-supporting protective film, transparent atleast where visual indicia is to appear therethrough, said protectivefilm providing an adhesive surface for contact with said printableoverlay, the adhesivity of said adhesive surface to said printableoverlay exceeding the adhesivity of the printable overlayer in directcontact with the exposed transparent portion of said self-supportingfilm but less than the adhesivity of the printable overlay for saidsecond masking surface and the adhesivity of said second masking surfacefor the exposed transparent portion of said self-supporting film.
 28. Atamperproof label construction as claimed in claim 21 in which: a. atleast part of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is incontact with a printable overlayer; and b. a second masking surface isin contact with a portion of said printable overlayer.
 29. A tamperprooflabel construction as claimed in claim 28 in combination with aself-supporting protective, transparent at least where visual indicia isto appear therethrough, said protective film having an adhesive surfacefor contact with said printable overlayer and said second maskingsurface, the adhesivity of said adhesive surface for said printableoverlay exceeding the adhesivity of said printable overlay for theexposed portion of said transparent film and less than the minimuminterlayer bond available from a laminate comprising said printableoverlay, said second masking surface and the exposed transparent portionof said self-supporting film.
 30. A composite tamperproof labelconstruction comprising: a. a self-supporting film at least a portion ofwhich is transparent and imprinted with visual indicia on at least onesurface of the transparent portion; b. a masking surface imprinted withvisual indicia in adhesive contact with at least one imprinted surfaceof the transparent portion of said self-supporting film; c. an adhesivelayer having a first adhesive surface in contact with said maskingsurface and the imprinted surface of the transparent portion of saidself-supporting film, the adhesion of said first adhesive surface forthe imprinted visual indicia on transparent portion of saidself-supporting surface exceeding the adhesion of the imprinted visualindicia for the transparent portion of said self-supporting film and asecond adhesive surface having a greater adhesion for a substrate towhich the label is to be applied than the adhesion of the imprintedvisual indicia for the transparent portion of said self-supporting film.31. A composite tamperproof label construction as claimed in claim 30 inwhich said masking surface is transparent and imprinted on the surfacethereof in contact with said adhesive layer.
 32. A composite tamperprooflabel construction as claimed in claim 30 in which: a. a part of thesurface of the exposed transparent portion oF the self-supporting filmopposed to the surface in contact with the masking surface is in contactwith a second masking surface; and b. a printable overlayer, at leasttransparent where visual indicia is to appear through the transparentportion of said self-supporting film, is in contact with the exposedtransparent portion of the self-supporting film and said second maskingsurface, the adhesivity of said printable overlayer for the exposedtransparent surface exceeding the maximum interlayer adhesion availablefrom the laminate comprising said printable overlayer, said secondmasking surface and the exposed transparent portion of saidself-supporting film.
 33. A composite tamperproof label as claimed inclaim 32 in combination with a self-supporting protective film,transparent at least where visual indicia is to appear therethrough,said protective film having an adhesive surface for contact with saidprintable overlayer, the adhesivity of said adhesive surface having agreater adhesivity for said printable overlayer than the maximuminterlayer adhesive bond provided by the laminate comprising theoverlayer, second masking surface and exposed transparent portion ofsaid self-supporting film, but less than the adhesivity of saidprintable overlayer for the exposed transparent surface
 34. A compositetamperproof label construction as claimed in claim 30 in which: a. partof the surface of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is inadhesive contact with a second masking surface; and b. a printableoverlay, at least transparent where visual indicia is to appear throughthe transparent portion of said self-supporting film, is in adhesivecontact with said second masking surface and in direct adhesive contactwith part of the exposed transparent portion of said self-supportingfilm.
 35. A composite tamperproof label construction as claimed in claim34 in combination with a self-supporting protective film, transparent atleast where visual indicia is to appear therethrough, said protectivefilm providing an adhesive surface for contact with said printableoverlay, the adhesivity of said adhesive surface to said printableoverlay exceeding the adhesivity of the printable overlayer in directcontact with the exposed transparent portion of said self-supportingfilm but less than the adhesivity of the printable overlay for saidsecond masking surface and the adhesivity of said second masking surfacefor the exposed transparent portion of said self-supporting film.
 36. Atamperproof label construction as claimed in claim 30 in which: a. atleast part of the exposed transparent portion of the self-supportingfilm opposed to the surface in contact with the masking surface is incontact with a printable overlayer; and b. a second masking surface isin contact with a portion of said printable overlayer.
 37. A tamperprooflabel construction as claimed in claim 36 in combination with aself-supporting protective, transparent at least where visual indicia isto appear therethrough, said protective film having an adhesive surfacefor contact with said printable overlayer and said second maskingsurface for contact with said printable overlayer and said secondmasking surface, the adhesivity of said adhesive surface for saidprintable overlay exceeding the adhesivity of said printable overlay forthe exposed portion of said transparent film and less than the minimuminterlayer bond available from a laminate comprising said printableoverlay, said second masking surface and the exposed transparent portionof said self-supporting film.
 38. A composite for construction of atamperproof label which comprises: a. a self-supporting film at least aportion of which is transparent and adapted to accept imprinting; b. atransparent masking surface in contact with part of the transparentportion of said self-supporting film said masking surface adapted toaccept imprInting; and c. an adhesive layer having a first adhesivesurface for contact with said self-supporting film and said maskingsurface, the adhesivity of said first adhesive surface for said maskingsurface exceeding the contact adherence of said masking surface for thetransparent portion of said self-supporting film and a second adhesivesurface adapted for contact to a substrate, the adhesivity of saidsecond adhesive surface for the substrate to which it is to be appliedexceeding the contact adherence of said masking surface for thetransparent portion of said self-supporting film.
 39. A composite forconstruction of a tamperproof label which comprises: a. aself-supporting film at least a portion of which is transparent andadapted to accept imprinting; b. a transparent masking surface inadhesive contact with part of the transparent portion of saidself-supporting film; said masking surface adapted to accept imprinting;and c. an adhesive layer having a first adhesive surface adapted forcontact with the transparent portion of said self-supporting film andsaid masking surface; the adhesion of said first adhesive surface for atleast one printable visual indicia exceeding the adhesivity of theprintable indicia for the transparent portion of said self-supportingfilm and a second adhesive surface for contact to a substrate, theadhesion of said second adhesive surface for the substrate to which itis to be applied exceeding the adhesivity of the printable indicia forthe transparent portion of said film.
 40. A composite for constructionof a tamperproof label which comprises: a. a self-supporting film atleast a portion of which is transparent and adapted to acceptimprinting; b. a transparent masking surface in adhesive contact withpart of the transparent portion of said self-supporting film; saidmasking surface adapted to accept imprinting; and c. an adhesive layerhaving a first adhesive surface adapted for contact with the transparentportion of said self-supporting film and said masking surface; theadhesion of said first adhesive surface for at least one printablevisual indicia exceeding the adhesivity of the printable indicia for thetransparent portion of said masking surface and a second adhesivesurface for contact to a substrate the adhesion of said second adhesivesurface for the substrate to which it is to be applied exceeding theadhesivity of the printable indicia for said masking surface.
 41. Acomposite for construction of a tamperproof label which comprises: a. aself-supporting film at least a portion of which is transparent andadapted to accept imprinting; b. a self-supporting masking surfaceadapted to be applied over a part of the transparent portion of saidself-supporting film; and c. an adhesive layer having a first adhesivesurface adapted for contact with the transparent portion of saidself-supporting film and said masking surface, the adhesivity of saidfirst adhesive surface for a visual indicia printable on the transparentportion of said self-supporting film exceeding the adhesivity of saidvisual indicia for said self-supporting film and a second adhesivesurface adapted for adhesive contact with a substrate, the adhesion ofsaid second adhesive surface to which it is to be applied exceeding theadhesivity of said visual indicia for the transparent portion of saidself-supporting film.